Constipation in pregnancy: prevalence, symptoms, and risk factors

Obstet Gynecol. 2007 Dec;110(6):1351-7. doi: 10.1097/01.AOG.0000295723.94624.b1.


Objective: To prospectively estimate constipation prevalence and risk factors in pregnancy.

Methods: We enrolled healthy pregnant women in this longitudinal study during the first trimester. At each trimester and 3 months postpartum, participants completed a self-administered bowel symptom questionnaire, physical activity and dietary fiber intake measures, and a prospective 7-day stool diary. Constipation was defined using the Rome II criteria (presence of at least two of the following symptoms for at least one quarter of defecations: straining, lumpy or hard stools, sensation of incomplete evacuation, sensation of anorectal obstruction, manual maneuvers to facilitate defecation, and fewer than three defecations per week). Generalized linear logistic models explored factors associated with constipation during pregnancy.

Results: One hundred three women were enrolled with mean (+/-standard deviation) age of 28 (+/-5) years; 54% were nulliparous and 92% white. Constipation prevalence rates were 24% (95% confidence interval [CI] 16-33%), 26% (95% CI 17-38%), 16% (95% CI 8-26%), and 24% (95% CI 13-36%) in the first, second, and third trimesters and 3 months postpartum, respectively. Additionally, irritable bowel syndrome (by Rome II criteria) prevalence rates were 19% (95% CI 12-28%), 13% (95% CI 6-23%), 13% (95% CI 6-23%) and 5% (95% CI 1-13%) in the first, second, and third trimesters and 3 months postpartum, respectively. In multivariable longitudinal analysis, iron supplements (OR 3.5, 95% CI 1.04-12.10) and past constipation treatment (OR 3.58, 95% CI 1.50-8.57) were associated with constipation during pregnancy.

Conclusion: Constipation measured using the Rome II criteria affects up to one fourth of women throughout pregnancy and at 3 months postpartum.

Level of evidence: II.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Constipation / epidemiology*
  • Constipation / pathology
  • Female
  • Humans
  • Iowa / epidemiology
  • Iron / adverse effects
  • Iron / therapeutic use
  • Longitudinal Studies
  • Postpartum Period
  • Pregnancy
  • Pregnancy Complications / epidemiology*
  • Pregnancy Complications / pathology
  • Pregnancy Trimesters
  • Prevalence
  • Prospective Studies
  • Risk Factors


  • Iron